Pateick mcdeemott



(No Model.)

P. MODERMOT'TJ KEY FOR PULLEYS.

No. 378,260. Patented Feb. 21, 1888;.

WITNEssEsi INVENIOR 7 m'w W9 UNITED STATEs PATENT rrrcn.

PATRICK MODERMOTT, OF MEMPHIS, TENNESSEE, ASSIGNOR TO THE MIL- BURN GINAND MACHINE COllIPANY, OF SAME PLACE.

KEY FOR PULLEYS.

SPECIFICATION forming part of Letters Patent No. 378,260, dated February21, 1888.

Application filed December 24,1886. Renewed September 7, 1887.

To all whom it may concern:

Be it known that I, PATRICK McDERMo'rT, of Memphis, in the county ofShelby and State of Tennessee, have invented a new and usefulImprovement in Keys for Pulleys, which im provement is fully set forthin the following specification and accompanying drawings, in whichFigure 1 is a side view of a wood split pul- IO ley equipped with one ofmy keys; Fig. 2, a perspective view of the cross bindingpieces, partlyin section; and Fig. 3, a detail view.

In the construction of what are known as woodsplit pulleys theparallelpieces which unite the arches or semicircles of which the pulleyis composed are provided with bolts, which cause these cross arms orpieces to bind tightly upon the shaft, and are thus held in position.For ordinary pulleys, or in cases "m where the ordinary amount of poweris transniitted,this fastening is sufficient and requires no groove andfeather; but in cases where the shaft is small and the pulley large orextraordinarily heavy and a great strain is exerted 2 5 it is better toprovide additional means to prevent'the pulley from turning on the axle;and the object of this invention is to provide a cheap and efficientmeans for accomplishing this purpose in such a manner that it can be 50readily applied by any ordinary mechanic.

The cross-bars A A are constructed in the ordinary manner, so far asrelates to their adjustment to the shaft, having centrally thesemicircular cross-grooves B to receive the 5 shaft 0 and the bolts DDfor binding the bars A to the shaft. On one side of the semicirculargroovesBthe cross-bars A are recessed out, as shown at E, and the key F,whose width is greater than the width of the recess, is fitted into thisrecessed space, made by matching the two bars together, as in Fig. 1,and suitable holes, F, are made in each cross- Serial No. 249,661. (Nomoth-l.)

bar to receive the bolts D. The key thus coir structed projects into thecircular space occupied by the shaft 0. In order, therefore, to attachthe key to the shaft, it is necessary to have a groove, G, chipped orplowed therein to receive the key. The same bolts, therefore, whichtighten the bars in clamping the shall; tighten the key F andpreventthepulley from turning.

It is obvious that the key may be fitted into the gains formed betweenthe bars A without necessitating the bolts D passing through the same,and in some cases such construction would be preferable; but in order toprevent the loss of the key, and also to add additional strength bymaking the key as wide as possibio, I prefer for all purposes to havethe bolts D pass through the key. It has sometimes heretofore been thepractice, for this general purpose, tov fit a collar or bushing to thecrossbars, owing to the fact that the wood adjacent to the shaft is moreor less likely to be worn away by the constant pressure or strain of thebolts D when in use. By the use of the key, however, a less pressure onthe part of the bolts is necessary to accomplish the same p'urpose,andin addition the simplicity and cheap ness are apparent.

Having described my in vcntion, what I claim as new is-- The combinationof the cross-bars, each grooved-and recessed as described, with the keyand the bolts passing through the bars and key, said key being adaptedto enter the groovein the shaft, substantially as described.

In testimony that I claim the foregoing I have hereunto set my hand,this 31st day of August, 1886, in the presence of witnesses.

PATRICK MGDEBMOTT.

\Vitnesses:

Hunsnon Gary, JOHN D. MILBURN.

